public class Calculator {
    double num1;
    double num2;
    public double plus(double num1,double num2){
        return num1+num2;
    }
    public double minus(double num1,double num2){
        return num1-num2;
    }
    public double multiplyBy(double num1,double num2){
        return num1*num2;
    }
    public double divide (double num1,double num2){
      if(num2==0)return 0;
      return num1/num2;
    }
}
